1. Field of the Invention
The present invention relates to a method of tempering edible compositions containing crystallizable fatty material, e.g. confections such as chocolate.
2. Description of the Prior Art
Confections such as chocolate contain crystalline fat when solid and, especially in the case of chocolate, this fat can be present in various polymorphic forms depending on how the confection has been cooled. In order that the confection has an acceptable texture and appearance, it is necessary to control the size and distribution of the fat crystals throughout the confection. This is normally done by a process of cooling the confection in its liquid state while stirring continuously to produce seed crystals of fat distributed through the mass of the confection. This process is referred to as tempering.
Chocolate tempering is commonly effected in an automatic tempering machine when the liquid chocolate is constantly stirred while being cooled to a temperature of about 27.degree.-29.degree. C., depending upon the type of chocolate, to promote the formation of fat crystals of a desired form and size. Following this, the chocolate, after slight heating to facilitate pumping, is passed to a depositor from where it is fed into molds. After molding, the chocolate is cooled to effect solidification. This type of process can have an adverse effect on the carefully developed fat crystal form and size with the result that a chocolate "bloom" can occur which detracts from the appearance of the chocolate. In an effort to mitigate this problem, it has been previously proposed in British patent specification Nos. 945083 and 1183125 to temper chocolate by supercooling it in the liquid form under high pressure while constantly stirring it to prevent solidification. In such a process, the chocolate is cooled to about 25.degree. C., has a low viscosity and is then immediately discharged into molds where it sets very quickly with minimal additional cooling.